On Saturday 17 April 2021 at 01:38 UTC, a CLDAP reflection targeted a fashion retail customer in Western Europe. The attack peaked at 253.8 Gbps and lasted 139 minutes. Traffic originated from 4013 autonomous systems in 90 countries, predominantly a rented booter service.
| Vector | CLDAP reflection |
| Peak | 253.8 Gbps |
| Duration | 139 min |
| Time to mitigation | 0.244 s |
| Attack traffic reaching origin | 0.063% |
| Legitimate traffic challenged | 0.45% |
Timeline
The attack was preceded by a hacktivist channel announcing the target. Edge packet filters identified the flood by source port and payload signature and dropped it at line rate across 38 points of presence.
What the customer saw
Checkout conversion was unchanged compared with the same hour of the previous week.
Recommendations
- Enable log streaming to your SIEM for faster correlation.
- Review allow-listed partner ranges quarterly.
- Lower challenge thresholds on authentication endpoints during high-risk events.
We moved from a scrubbing provider to always-on last year; time to mitigation went from minutes to basically nothing.
Interesting that most attacks are under ten minutes. Our experience is similar.
We moved from a scrubbing provider to always-on last year; time to mitigation went from minutes to basically nothing.